Oil pump control system for vehicle

ABSTRACT

An oil pump control system for a vehicle, may include an oil pump configured to supply oil to an engine, an oil pressure control valve regulating oil pressure value of a discharging part in the oil pump, an oil pressure sensor sensing and outputting the oil pressure value of the discharging part in the oil pump, and a controller receiving a signal of the oil pressure value, determining a target oil pressure value of the discharging part in the oil pump in response to information relating to an oil pressure and operation state of the engine among vehicle information inputted from outside, comparing the sensed oil pressure value inputted from the oil pressure sensor with the target oil pressure value, and performing feedback control to drive the oil pressure control valve.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application claims priority to Korean Patent ApplicationNumber 10-2011-133541 filed Dec. 13, 2011, the entire contents of whichapplication is incorporated herein for all purposes by this reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an oil pump control system for avehicle, and more particularly, to an oil pump control system for avehicle, which controls oil pressure of a discharging part of an oilpump.

2. Description of Related Art

FIG. 1 is a block diagram of an oil pump control system for a vehicleaccording to the related art. As illustrated in FIG. 1, control pumpcontrol system 1 according to the related art includes an oil pump 10driven by a crankshaft and a relief valve 20 for returning oil to asuction port of the pump when oil pressure excessively increases.

Here, relief valve 20 operates to recirculate oil of a discharging partof oil pump 10 to a suction part of oil pump 10 when an oil-pumpdischarge pressure applied to the top surface of a plunger 22 is largerthan a support force of a spring 24 supporting plunger 22.

As such, since relief valve 20 is opened and closed by such a mechanicaloperation as described above, there is a limitation in activelycontrolling the oil pressure of the discharging part of oil pump 10 inresponse to an engine operation condition, oil temperature, watertemperature or the like.

Accordingly, even when an unnecessary oil pressure is formed in thedischarging part of oil pump 10 during cold working or a high or lowload, oil pump control system 1 according to the related art hasdifficulties in properly managing the unnecessary oil pressure.Furthermore, such a problem increases the load of oil pump 10, therebyreducing fuel efficiency.

The information disclosed in this Background of the Invention section isonly for enhancement of understanding of the general background of theinvention and should not be taken as an acknowledgement or any form ofsuggestion that this information forms the prior art already known to aperson skilled in the art.

BRIEF SUMMARY

Various aspects of the present invention are directed to provide an oilpump control system for a vehicle, which is capable of activelycontrolling the oil pressure of a discharging part of an oil pump inresponse to an operation condition of the vehicle and environmentchanges, using a relief valve which may be electrically controlledinstead of a mechanical relief valve in the related art.

In an aspect of the present invention, an oil pump control system for avehicle, may include an oil pump configured to supply oil to an engine,an oil pressure control valve regulating oil pressure value of adischarging part in the oil pump, an oil pressure sensor sensing andoutputting the oil pressure value of the discharging part in the oilpump, and a controller receiving a signal of the oil pressure value,determining a target oil pressure value of the discharging part in theoil pump in response to information relating to an oil pressure andoperation state of the engine among vehicle information inputted fromoutside, comparing the sensed oil pressure value inputted from the oilpressure sensor with the target oil pressure value, and performingfeedback control to drive the oil pressure control valve.

The controller may include a first control module determining the targetoil pressure value according to a first target oil pressure map which isset in a preset range in response to speed and fuel amount of the engineamong the vehicle information.

The target oil pressure value determined by the first target oilpressure map is corrected by oil temperature and cooling watertemperature among the vehicle information.

The controller may further include a second control module determiningthe target oil pressure value according to a second target oil pressuremap, which is set in response to the speed and the fuel amount of theengine among the vehicle information, in consideration of opening of apiston cylinder cooling jet for supplying oil transferred from the oilpump to a piston of the engine, and a third control module controllingthe piston cylinder cooling jet in response to the speed and the fuelamount of the engine, wherein an opening signal of the piston cylindercooling jet is inputted, the controller deactivates the first controlmodule and activates the second and third control modules.

The controller may further include an engine failure warning modulewhich, when a difference between the target oil pressure value and thesensed oil pressure value approaches a preset failure critical value,outputs a warning signal to the outside as an engine failure.

The feedback control is implemented by proportional integral (PI)control or proportional integral derivative (PID) control.

As such, the oil pump control system for a vehicle according to theexemplary embodiment of the present invention calculates the target oilpressure value of the discharging part of the oil pump in response tothe information relating to the oil pressure and operation state of theengine among the vehicle information, and performs feedback control suchthat the measured oil pressure value inputted from the oil pressuresensor follows the target oil pressure value. Therefore, the oil pumpcontrol system may control the formation of unnecessary oil pressure inthe discharging part of the oil pump during cold working or a high orlow load, thereby managing the load of the oil pump. Accordingly, it ispossible to prevent the reduction of fuel efficiency caused by the oilpump.

Further, the oil pump control system for a vehicle according to theexemplary embodiment of the present invention may perform feedbackcontrol according to the target oil pressure value calculated byconsidering the effect of the piston cylinder cooling jet, which makesit possible to further maximize the fuel efficiency.

In addition, the oil pump control system for a vehicle according to theexemplary embodiment of the present invention may detect an oil pressuredifference of the engine and quickly determine a failure caused by afatal error of an engine lubricating system, thereby preventing anengine failure.

The methods and apparatuses of the present invention have other featuresand advantages which will be apparent from or are set forth in moredetail in the accompanying drawings, which are incorporated herein, andthe following Detailed Description of the Invention, which togetherserve to explain certain principles of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram of an oil pump control system for a vehicleaccording to the related art.

FIG. 2 is a block diagram of an oil pump control system for a vehicleaccording to an exemplary embodiment of the present invention.

FIG. 3 is a block diagram of an oil pump control system for a vehicleaccording to another exemplary embodiment of the present invention.

It should be understood that the appended drawings are not necessarilyto scale, presenting a somewhat simplified representation of variousfeatures illustrative of the basic principles of the invention. Thespecific design features of the present invention as disclosed herein,including, for example, specific dimensions, orientations, locations,and shapes will be determined in part by the particular intendedapplication and use environment.

In the figures, reference numbers refer to the same or equivalent partsof the present invention throughout the several figures of the drawing.

DETAILED DESCRIPTION

Reference will now be made in detail to various embodiments of thepresent invention(s), examples of which are illustrated in theaccompanying drawings and described below. While the invention(s) willbe described in conjunction with exemplary embodiments, it will beunderstood that present description is not intended to limit theinvention(s) to those exemplary embodiments. On the contrary, theinvention(s) is/are intended to cover not only the exemplaryembodiments, but also various alternatives, modifications, equivalentsand other embodiments, which may be included within the spirit and scopeof the invention as defined by the appended claims.

Hereinafter, an oil pump control system for a vehicle according to anexemplary embodiment of the present invention will be described withreference to the accompanying drawings.

Referring to FIG. 2, an oil pump control system 100 for a vehicleaccording to the exemplary embodiment of the present invention will bedescribed. FIG. 2 is a block diagram of the oil pump control system fora vehicle according to the exemplary embodiment of the presentinvention.

Oil pump control system 100 for a vehicle according to the exemplaryembodiment of the present invention may include an oil pump 110, an oilpressure control valve 112, an oil pressure sensor 113, and a controller130.

Oil pump 110 pumps oil of an oil pan 116 through a suction part 114 anddischarges the pumped oil to a discharging part 118. Oil pump 110 isdriven in proportion to the speed of an engine. The oil dischargedthrough discharging part 118 is supplied into the engine.

Oil pressure control valve 112 is a valve for controlling the oilpressure of discharging part 118, and disposed in a flow path betweensuction part 114 and discharging part 118. Oil pressure control valve112 may include a solenoid valve driven by the control of controller130.

Oil pressure sensor 113 senses the oil pressure of discharging part 118of oil pump 130 and outputs the sensed oil pressure value to controller130. Accordingly, oil pressure sensor 113 may supply an actual oilpressure value, obtained by the control of controller 130, to controller130.

Controller 130 calculates a target oil pressure value which dischargingpart 118 is to maintain, in response to information relating to the oilpressure and operation state of the engine among a variety of vehicleinformation inputted from various sensors disposed in the vehicle. Then,controller 130 compares the measured oil pressure value inputted fromoil pressure sensor 113 with the calculated target oil pressure valueand performs feedback control for driving oil pressure control valve 112to follow the reference target oil pressure value. Here, the feedbackcontrol may be implemented by proportional integral (PI) control orproportional integral derivative (PID) control.

As illustrated in FIG. 2, controller 130 may be divided into a firstcontrol module 132 for calculating the target oil pressure value, a PIcontrol module 137 for performing PI control to drive oil pressurecontrol valve 112 to follow the target oil pressure value, and an enginefailure warning module 139.

First control module 132 may calculate the target oil pressure valueaccording to a first target oil pressure map 1322 which is set inresponse to the speed and fuel amount of the engine among the vehicleinformation. Here, the target oil pressure value calculated by firsttarget oil pressure map 1322 may be corrected by oil temperature andcooling water temperature among the vehicle information. The target oilpressure value set in response to the speed and fuel amount of theengine by first target oil pressure map 1322 is set in a preset rangewhere the oil pressure of discharging part 118 of oil pump 130 is notexcessively formed.

PI control module 137 compares the measured oil pressure value inputtedfrom oil pressure sensor 113 with the target oil pressure valuecalculated and corrected by first control module 132 and performs PIfeedback control to drive the oil pressure control valve such that theactual oil pressure of discharging part 118 follows the target oilpressure value calculated by first control module 132.

As such, oil pump control system 100 for a vehicle according to theexemplary embodiment of the present invention calculates the target oilpressure value of discharging part 118 of oil pump 130 in response tothe information relating to the oil pressure and operation state of theengine among the vehicle information, and operates PI control module 137such that the measured oil pressure value inputted from oil pressuresensor 113 follows the target oil pressure value. Accordingly, oil pumpcontrol system 100 for a vehicle may control the formation ofunnecessary oil pressure in discharging part 118 of oil pump 130 duringcold working or a high or low load, thereby managing the load of oilpump 130. Accordingly, it is possible to prevent the reduction of thefuel efficiency caused by oil pump 130.

When a difference between the target oil pressure value by first controlmodule 132 and the measured oil pressure inputted from oil pressuresensor 13 approaches a preset failure critical value, engine failurewarning module 139 may consider this state as an engine failure, andoutput a corresponding warning signal to the outside.

Oil pump control system 100 for a vehicle according to the exemplaryembodiment of the present invention may detect the oil pressuredifference of the engine and quickly determine a failure caused by afatal error of an engine lubricating system, thereby preventing anengine failure.

Hereinafter, referring to FIG. 3, an oil pump control system 200 for avehicle according to another exemplary embodiment of the presentinvention will be described.

As illustrated in FIG. 3, oil pump 210 pumps oil of an oil pan 216through a suction part 214 and discharges the pumped oil to adischarging part 218.

A controller 230 of oil pump control system 200 for a vehicle accordingto the exemplary embodiment of the present invention may include asecond control module 234 and a third control module 236 in addition toa first control module 232, a PI control module 237 to drive oilpressure control valve 212, and an engine failure warning module 239,unlike the above-described exemplary embodiment. Here, first controlmodule 232 and second control module 234 are selectively operated by thecontrol of controller 230.

That is, when an opening signal of a piston cylinder cooling jet isinputted, controller 230 may deactivate first control module 232,activate second control module 234 and third control module 236, andcontrol the oil pressure according to a second valve duty map 2342considering an effect of the piston cylinder cooling jet.

When the opening signal of the piston cylinder cooling jet is notinputted, that is, when the piston cylinder cooling jet is closed, firstcontrol module 232 may calculate a target oil pressure value of adischarging part 218 according to a first target oil pressure map 2322considering the effect of the piston cylinder cooling jet.

Here, second control module 234 may calculate the target oil pressurevalue according to a second target oil pressure map 2342 and output thecalculated target oil pressure value to PI control module 237. Secondtarget oil pressure map 2342 is set in response to the speed and fuelamount of the engine among the vehicle speed such that the target oilpressure value of discharging part 218 is calculated within a presetrange, in consideration of the opening of the piston cylinder coolingjet. Here, the piston cylinder cooling jet supplies oil transferred fromoil pump 210 to a piston of the engine.

Second control module 234 may correct a control signal generated bysecond target oil pressure map 2342 according to oil temperature andcooling water temperature among the vehicle information.

PI control module 237 compares a measured oil pressure value inputtedfrom oil pressure sensor 213 with the target oil pressure valuecalculated and corrected by second control module 234, and performs PIfeedback control for driving the oil pressure control valve such thatthe actual oil pressure of discharging part 218 follows the target oilpressure value of first control module 232.

Third control module 236 may control the piston cylinder cooling jet inresponse to the speed and fuel amount of the engine among the vehicleinformation. Third control module 236 may include a cooling jet controlmap 2362 in which a control signal value for controlling the pistoncylinder cooling jet is set by the speed and fuel amount of the engineamong the vehicle information. Third control module 236 may control thepiston cylinder cooling jet according to cooling jet control map 2362.

When an opening signal of the piston cylinder cooling jet is inputted,controller 230 may deactivate first control module 232, and activatesecond and third control modules 234 and 236.

As such, oil pump control system 200 for a vehicle according to theexemplary embodiment of the present invention may calculate a target oilpressure value, which is more precise than in the exemplary embodimentillustrated in FIG. 2, through second control module 234 which reflectsan oil pressure change of discharging part 218 of oil pump 210 when thepiston cylinder cooling jet is opened.

Therefore, control system 200 according to the exemplary embodiment ofthe present invention may perform feedback control according to thetarget oil pressure value calculated by considering the effect of thepiston cylinder cooling jet, which makes it possible to further maximizethe fuel efficiency than in the exemplary embodiment of FIG. 2.

The foregoing descriptions of specific exemplary embodiments of thepresent invention have been presented for purposes of illustration anddescription. They are not intended to be exhaustive or to limit theinvention to the precise forms disclosed, and obviously manymodifications and variations are possible in light of the aboveteachings. The exemplary embodiments were chosen and described in orderto explain certain principles of the invention and their practicalapplication, to thereby enable others skilled in the art to make andutilize various exemplary embodiments of the present invention, as wellas various alternatives and modifications thereof. It is intended thatthe scope of the invention be defined by the Claims appended hereto andtheir equivalents.

What is claimed is:
 1. An oil pump control system for a vehicle,comprising: an oil pump configured to supply oil to an engine; an oilpressure control valve regulating oil pressure value of a dischargingpart in the oil pump; an oil pressure sensor sensing and outputting theoil pressure value of the discharging part in the oil pump; and acontroller receiving a signal of the oil pressure value, determining atarget oil pressure value of the discharging part in the oil pump inresponse to information relating to an oil pressure and operation stateof the engine among vehicle information inputted from outside, comparingthe sensed oil pressure value inputted from the oil pressure sensor withthe target oil pressure value, and performing feedback control to drivethe oil pressure control valve.
 2. The oil pump control system asdefined in claim 1, wherein the controller comprises a first controlmodule determining the target oil pressure value according to a firsttarget oil pressure map which is set in a preset range in response tospeed and fuel amount of the engine among the vehicle information. 3.The oil pump control system as defined in claim 2, wherein the targetoil pressure value determined by the first target oil pressure map iscorrected by oil temperature and cooling water temperature among thevehicle information.
 4. The oil pump control system as defined in claim2, wherein the controller further comprises: a second control moduledetermining the target oil pressure value according to a second targetoil pressure map, which is set in response to the speed and the fuelamount of the engine among the vehicle information, in consideration ofopening of a piston cylinder cooling jet for supplying oil transferredfrom the oil pump to a piston of the engine; and a third control modulecontrolling the piston cylinder cooling jet in response to the speed andthe fuel amount of the engine, wherein an opening signal of the pistoncylinder cooling jet is inputted, the controller deactivates the firstcontrol module and activates the second and third control modules. 5.The oil pump control system as defined in claim 1, wherein thecontroller further comprises an engine failure warning module which,when a difference between the target oil pressure value and the sensedoil pressure value approaches a preset failure critical value, outputs awarning signal to the outside as an engine failure.
 6. The oil pumpcontrol system as defined in claim 1, wherein the feedback control isimplemented by proportional integral (PI) control or proportionalintegral derivative (PID) control.